#include<bits/stdc++.h>
using namespace std;
int n,a[100010],cnt;
bool used[100010],rq[100010];
void check(int x){
    if(x>=n)return;
    if(rq[a[x]])return;
    int y=1;
    while(a[x+y]==a[x]||used[x+y]){
        y++;
    }
    if(x+y>n){
        rq[a[x]]=1;
    }
    used[x+y]=1;
    check(x+y);
}
int main(){
freopen("duel.in","r",stdin);
freopen("duel.out","w",stdout);
ios::sync_with_stdio(false);
cin>>n;
for(int i=1;i<=n;i++){
    cin>>a[i];
}
sort(a+1,a+n+1);
for(int i=1;i<=n;i++){
    if(!used[i]){
        check(i);
        cnt++;
    }
}
cout<<cnt;
return 0;
}
